Electrical connectors are conductive bridges that join portions of electrical circuits. Some connectors are temporary bridges and are interfaces between different elements in a system, such as connectors on a rear panel of electrical components in large systems. Hundreds of types of electrical connectors exist on the market. One familiar type of connector is the quick-fit connector used at both ends of a wire used to either connect a television to a local cable or antenna, the television to a recording device, or a keyboard to a computer. Each of these cables has at both ends a male connector (a plug) and a female connector (a jack) bridged to the cable on which they are mounted.
Because of a need for the electrical equipment designed by a wide range of providers to interface properly with other devices designed by different firms, connectors at their interfaces are often forced to meet agreed-upon technical standards. For example, some of the most common types of connectors include the phone line 8P8C connector, the serial computer connector DE-9, the Universal Serial Bus (USB) connector for the connection of memory cards to most computers, and Radio Frequency (RF) connectors such as the cable connector designed to main impedance in the line. Any rugged, polarized connector improvement must not interfere with the capacity of the connector to meet technical standards.
RF connectors are electrical connectors designed to work at radio frequencies in the multimegahertz range. RF connectors are typically used on coaxial cables and are designed to maintain constant shielding over the length of the connector. Mechanical fasteners made of mating male and female ends are often called the plug and the jack. At the ends, or interfaces, threads, bayonets, braces, pull-push, springs, or any other locking mechanism is used to hold the plug to the jack so the coaxial cable of the RF connector is electrically connected.
For example, wireless transceivers operate mostly in electrical systems using RF connectors. Many different types of RF connectors have been created over the years, such as, for example, standard connectors (7/16 DIN, BNC, C, Dezifix, F, HN, IEC 169-2, LC, Motorola, Musa, NMO, N, SC, TNC, UHR), miniature connectors (M-BNC, M-UHF, DIN 47223, U.FL, and SMZ), subminiature connectors (MMCX, MCX, FME, SMA, SMB, SMC, and SMP), precision connectors (APC-7), flange connectors (EIA RF), and even quick-lock connectors (QMA, QLS, SnapN, and CQMA).
As an improvement to threaded RF connectors, such as the SMA connector with ring on the jack that is rotated clockwise over the threads on a plug for coupling, snap-on connectors such as the QMA connectors are improved types of SMA connectors where the jack in pushed against a face of the plug and small radial legs are bent out until they clip back in a groove that is off-set from the face of the connector. To release the QMA connector, the user must move an external ring on the connector until the radial legs are bent out to release the groove.
These connectors, when mounted on a RF coaxial cable, have radial symmetry (i.e., the jack does not need to be specifically oriented). Only connectors mounted on cables with a multitude of conductors lose part of this radial symmetry. Standardized connectors, aside from the power category of electrical connectors, are not polarized; any plug can be mounted on any jack as long as the radius of the connectors are the same. A connector with four internal conductors where each conductor is arranged in a square configuration, each located on the outer corners of the configuration, remove all but four angles of radial symmetry to the connector (i.e., the jack can be oriented at four different orientations compared to the mated plug). Even when a portion of the radial symmetry is compromised, any standardized jack can still be mounted on any standardized plug.
RCA connectors, or audio/video connectors used to connect components to a monitor, uses a color code (yellow is video, white and red are audio) to distinguish between the nonpolarized cables. One obvious problem associated with this polarization technology is the need to view colors and have visual access to all plugs often located in hard-to-reach areas. In addition, even when visual access is possible, human error is still possible. In cases when equipment is damaged if the conductors are misconnected, or when it is difficult to gain access to the connectors to change the connections, what is needed is a system that is polarized and free of inherent problems associated with visual polarization.
One other possible solution is shown in FIGS. 1A-1B where a threaded jack is equipped with an external ring having longitudinal slots on the external surface of the ring. A second ring is mounted on the plug and has a series of angled tabs (shown as three tabs at 120°) that slide into the longitudinal slots as the connector is screwed in. This device does not teach displacing the different slots at different angles to polarize the connectors. The system uses tabs interlock the rugged components of the described connector. This system can be mounted only on threaded connectors, not snap-in connectors. This technology cannot be used without aid. With time and fatigue, the angled tabs of the device may be forced in and users can damage the external surface of the jack between the slots as the rings are turned.
What is needed is a simple polarization system for plugs and jacks that can be operated without visual help but instead with a user's manual touch where a very large quantity of polarized configurations can coexist without risk of damaging any element of the connector as the parts wear and fatigue.
Another inherent problem of these connectors is the weakness to shock of both the plug and the jack. The plug generally sticks out from the mounting plate and is of low weight compared to the equipment to which it may be attached. If the equipment to which the jack is mounted is dropped or impacted with the environment, or if a person steps on the plug as it rests on the ground while repairs are conducted, the connector is damaged. As a consequence, equipment designers when possible protect the plugs by placing them in recessed or remote areas of the electrical device on which they are mounted. Recessed plugs are difficult to view and access, compounding the problems associated with visual polarization. Other protection equipment such as bars can be attached to the surrounding structures to protect the plugs. The device shown in FIGS. 1A-B, for example, is not rugged. What is needed is a system capable of protecting the connector within a polarized plug-and-jack environment.